/* $Id$
 *
 * COPYRIGHT:              See COPYING in the top level directory
 * PROJECT:                ReactOS kernel
 * FILE:                   ntoskrnl/ps/thread.c
 * PURPOSE:                Thread managment
 * PROGRAMMER:             David Welch (welch@mcmail.com)
 * REVISION HISTORY: 
 *               23/06/98: Created
 *               12/10/99: Phillip Susi:  Thread priorities, and APC work
 *               09/08/03: Skywing:       ThreadEventPair support (delete)
 */

/*
 * NOTE:
 * 
 * All of the routines that manipulate the thread queue synchronize on
 * a single spinlock
 * 
 */

/* INCLUDES ****************************************************************/

#define NTOS_MODE_KERNEL
#include <ntos.h>
#include <internal/ke.h>
#include <internal/ob.h>
#include <internal/ps.h>
#include <internal/ex.h>
#include <internal/se.h>
#include <internal/id.h>
#include <internal/dbg.h>
#include <internal/ldr.h>

#define NDEBUG
#include <internal/debug.h>

/* GLOBAL *******************************************************************/

static ULONG PiNextThreadUniqueId = 0;

extern KSPIN_LOCK PiThreadListLock;
extern ULONG PiNrThreads;

extern LIST_ENTRY PiThreadListHead;

#ifndef LIBCAPTIVE
#define MAX_THREAD_NOTIFY_ROUTINE_COUNT    8

static ULONG PiThreadNotifyRoutineCount = 0;
static PCREATE_THREAD_NOTIFY_ROUTINE
PiThreadNotifyRoutine[MAX_THREAD_NOTIFY_ROUTINE_COUNT];
#endif /* LIBCAPTIVE */

/* FUNCTIONS ***************************************************************/

#ifndef LIBCAPTIVE

NTSTATUS STDCALL
PsAssignImpersonationToken(PETHREAD Thread,
			   HANDLE TokenHandle)
{
   PACCESS_TOKEN Token;
   SECURITY_IMPERSONATION_LEVEL ImpersonationLevel;
   NTSTATUS Status;
   
   if (TokenHandle != NULL)
     {
	Status = ObReferenceObjectByHandle(TokenHandle,
					   0,
					   SepTokenObjectType,
					   UserMode,
					   (PVOID*)&Token,
					   NULL);
	if (!NT_SUCCESS(Status))
	  {
	     return(Status);
	  }
	ImpersonationLevel = Token->ImpersonationLevel;
     }
   else
     {
	Token = NULL;
	ImpersonationLevel = 0;
     }
   
   PsImpersonateClient(Thread,
		       Token,
		       0,
		       0,
		       ImpersonationLevel);
   if (Token != NULL)
     {
	ObDereferenceObject(Token);
     }
   return(STATUS_SUCCESS);
}

/*
 * @implemented
 */
VOID STDCALL
PsRevertToSelf(VOID)
{
   PETHREAD Thread;

   Thread = PsGetCurrentThread();

   if (Thread->ActiveImpersonationInfo != 0)
     {
	ObDereferenceObject(Thread->ImpersonationInfo->Token);
	Thread->ActiveImpersonationInfo = 0;
     }
}

/*
 * @implemented
 */
VOID STDCALL
PsImpersonateClient(PETHREAD Thread,
		    PACCESS_TOKEN Token,
		    UCHAR b,
		    UCHAR c,
		    SECURITY_IMPERSONATION_LEVEL Level)
{
   if (Token == 0)
     {
	if (Thread->ActiveImpersonationInfo != 0)
	  {
	     Thread->ActiveImpersonationInfo = 0;
	     if (Thread->ImpersonationInfo->Token != NULL)
	       {
		  ObDereferenceObject(Thread->ImpersonationInfo->Token);
	       }
	  }
	return;
     }
   if (Thread->ActiveImpersonationInfo == 0 ||
       Thread->ImpersonationInfo == NULL)
     {
	Thread->ImpersonationInfo = ExAllocatePool(NonPagedPool,
      					   sizeof(PS_IMPERSONATION_INFO));	
     }
   Thread->ImpersonationInfo->Level = Level;
   Thread->ImpersonationInfo->Unknown2 = c;
   Thread->ImpersonationInfo->Unknown1 = b;
   Thread->ImpersonationInfo->Token = Token;
   ObReferenceObjectByPointer(Token,
			      0,
			      SepTokenObjectType,
			      KernelMode);
   Thread->ActiveImpersonationInfo = 1;
}

PACCESS_TOKEN
PsReferenceEffectiveToken(PETHREAD Thread,
			  PTOKEN_TYPE TokenType,
			  PUCHAR b,
			  PSECURITY_IMPERSONATION_LEVEL Level)
{
   PEPROCESS Process;
   PACCESS_TOKEN Token;
   
   if (Thread->ActiveImpersonationInfo == 0)
     {
	Process = Thread->ThreadsProcess;
	*TokenType = TokenPrimary;
	*b = 0;
	Token = Process->Token;
     }
   else
     {
	Token = Thread->ImpersonationInfo->Token;
	*TokenType = TokenImpersonation;
	*b = Thread->ImpersonationInfo->Unknown2;
	*Level = Thread->ImpersonationInfo->Level;	
     }
   return(Token);
}

NTSTATUS STDCALL
NtImpersonateThread(IN HANDLE ThreadHandle,
		    IN HANDLE ThreadToImpersonateHandle,
		    IN PSECURITY_QUALITY_OF_SERVICE SecurityQualityOfService)
{
   PETHREAD Thread;
   PETHREAD ThreadToImpersonate;
   NTSTATUS Status;
   SECURITY_CLIENT_CONTEXT ClientContext;
   
   Status = ObReferenceObjectByHandle(ThreadHandle,
				      0,
				      PsThreadType,
				      UserMode,
				      (PVOID*)&Thread,
				      NULL);
   if (!NT_SUCCESS(Status))
     {
	return(Status);
     }
   
   Status = ObReferenceObjectByHandle(ThreadToImpersonateHandle,
				      0,
				      PsThreadType,
				      UserMode,
				      (PVOID*)&ThreadToImpersonate,
				      NULL);
   if (!NT_SUCCESS(Status))
     {
	ObDereferenceObject(Thread);
	return(Status);
     }
   
   Status = SeCreateClientSecurity(ThreadToImpersonate,
				   SecurityQualityOfService,
				   0,
				   &ClientContext);
   if (!NT_SUCCESS(Status))
     {
	ObDereferenceObject(Thread);
	ObDereferenceObject(ThreadToImpersonate);
	return(Status);
     }
   
   SeImpersonateClient(&ClientContext, Thread);
   if (ClientContext.Token != NULL)
     {
	ObDereferenceObject(ClientContext.Token);
     }
   return(STATUS_SUCCESS);
}

NTSTATUS STDCALL
NtOpenThreadToken(IN	HANDLE		ThreadHandle,  
		  IN	ACCESS_MASK	DesiredAccess,  
		  IN	BOOLEAN		OpenAsSelf,     
		  OUT	PHANDLE		TokenHandle)
{
#if 0
   PETHREAD Thread;
   NTSTATUS Status;
   PACCESS_TOKEN Token;
   
   Status = ObReferenceObjectByHandle(ThreadHandle,
				      0,
				      PsThreadType,
				      UserMode,
				      (PVOID*)&Thread,
				      NULL);
   if (!NT_SUCCESS(Status))
     {
	return(Status);
     }
   
   Token = PsReferencePrimaryToken(Thread->ThreadsProcess);
   SepCreateImpersonationTokenDacl(Token);
#endif
   return(STATUS_UNSUCCESSFUL);
}

#endif /* LIBCAPTIVE */

/*
 * @implemented
 */
PACCESS_TOKEN STDCALL 
PsReferenceImpersonationToken(PETHREAD Thread,
			      PULONG Unknown1,
			      PULONG Unknown2,
			      SECURITY_IMPERSONATION_LEVEL* Level)
{
   if (Thread->ActiveImpersonationInfo == 0)
     {
	return(NULL);
     }
   
#ifdef LIBCAPTIVE
   KeBugCheck(0);
	 /* NOTREACHED */
	 return NULL;
#else /* !LIBCAPTIVE */
   *Level = Thread->ImpersonationInfo->Level;
   *Unknown1 = Thread->ImpersonationInfo->Unknown1;
   *Unknown2 = Thread->ImpersonationInfo->Unknown2;
   ObReferenceObjectByPointer(Thread->ImpersonationInfo->Token,
			      TOKEN_ALL_ACCESS,
			      SepTokenObjectType,
			      KernelMode);
   return(Thread->ImpersonationInfo->Token);
#endif /* LIBCAPTIVE */
}

#ifndef LIBCAPTIVE

VOID
PiBeforeBeginThread(CONTEXT c)
{
   KeLowerIrql(PASSIVE_LEVEL);
}

VOID STDCALL
PiDeleteThread(PVOID ObjectBody)
{
  KIRQL oldIrql;
  PETHREAD Thread;
  ULONG i;
  PCREATE_THREAD_NOTIFY_ROUTINE NotifyRoutine[MAX_THREAD_NOTIFY_ROUTINE_COUNT];
  ULONG NotifyRoutineCount;

  Thread = (PETHREAD)ObjectBody;

  DPRINT("PiDeleteThread(ObjectBody %x)\n",ObjectBody);

  /* Terminate Win32 thread */
  PsTerminateWin32Thread (Thread);

  ObDereferenceObject(Thread->ThreadsProcess);
  Thread->ThreadsProcess = NULL;

  KeAcquireSpinLock(&PiThreadListLock, &oldIrql);
  for (i = 0; i < PiThreadNotifyRoutineCount; i++)
  {
     NotifyRoutine[i] = PiThreadNotifyRoutine[i];
  }
  NotifyRoutineCount = PiThreadNotifyRoutineCount;
  PiNrThreads--;
  RemoveEntryList(&Thread->Tcb.ThreadListEntry);
  KeReleaseSpinLock(&PiThreadListLock, oldIrql);
  ExpSwapThreadEventPair(Thread, NULL); /* Release the associated eventpair object, if there was one */

  for (i = 0; i < NotifyRoutineCount; i++)
  {
     //must be called below DISPATCH_LVL
     NotifyRoutine[i](Thread->Cid.UniqueProcess,
                      Thread->Cid.UniqueThread,
                      FALSE);
  }

  KeReleaseThread(Thread);
  DPRINT("PiDeleteThread() finished\n");
}

#endif /* LIBCAPTIVE */

NTSTATUS
PsInitializeThread(HANDLE ProcessHandle,
		   PETHREAD* ThreadPtr,
		   PHANDLE ThreadHandle,
		   ACCESS_MASK	DesiredAccess,
		   POBJECT_ATTRIBUTES ThreadAttributes,
		   BOOLEAN First)
{
   PETHREAD Thread;
   NTSTATUS Status;
   KIRQL oldIrql;
   PEPROCESS Process;
#ifndef LIBCAPTIVE
   ULONG i;
   ULONG NotifyRoutineCount;
   PCREATE_THREAD_NOTIFY_ROUTINE NotifyRoutine[MAX_THREAD_NOTIFY_ROUTINE_COUNT];
#endif /* LIBCAPTIVE */

   /*
    * Reference process
    */
   if (ProcessHandle != NULL)
     {
	Status = ObReferenceObjectByHandle(ProcessHandle,
					   PROCESS_CREATE_THREAD,
					   PsProcessType,
					   UserMode,
					   (PVOID*)&Process,
					   NULL);
	if (Status != STATUS_SUCCESS)
	  {
	     DPRINT("Failed at %s:%d\n",__FILE__,__LINE__);
	     return(Status);
	  }
	DPRINT( "Creating thread in process %x\n", Process );
     }
   else
     {
	Process = PsInitialSystemProcess;
	ObReferenceObjectByPointer(Process,
				   PROCESS_CREATE_THREAD,
				   PsProcessType,
				   UserMode);
     }
   
   /*
    * Create and initialize thread
    */
   Status = ObRosCreateObject(ThreadHandle,
			   DesiredAccess,
			   ThreadAttributes,
			   PsThreadType,
			   (PVOID*)&Thread);
   if (!NT_SUCCESS(Status))
     {
	return(Status);
     }

   DPRINT("Thread = %x\n",Thread);
   
   PiNrThreads++;
   
   KeInitializeThread(&Process->Pcb, &Thread->Tcb, First);
   Thread->ThreadsProcess = Process;
   /*
    * FIXME: What lock protects this?
    */
   InsertTailList(&Thread->ThreadsProcess->ThreadListHead, 
		  &Thread->Tcb.ProcessThreadListEntry);
   InitializeListHead(&Thread->TerminationPortList);
   KeInitializeSpinLock(&Thread->ActiveTimerListLock);
   InitializeListHead(&Thread->IrpList);
   Thread->Cid.UniqueThread = (HANDLE)InterlockedIncrement(
					      (LONG *)&PiNextThreadUniqueId);
   Thread->Cid.UniqueProcess = (HANDLE)Thread->ThreadsProcess->UniqueProcessId;
   Thread->DeadThread = 0;
   Thread->Win32Thread = 0;
   DPRINT("Thread->Cid.UniqueThread %d\n",Thread->Cid.UniqueThread);
   
   *ThreadPtr = Thread;
   
   KeAcquireSpinLock(&PiThreadListLock, &oldIrql);
   InsertTailList(&PiThreadListHead, &Thread->Tcb.ThreadListEntry);
#ifndef LIBCAPTIVE
   for (i = 0; i < PiThreadNotifyRoutineCount; i++)
   {
      NotifyRoutine[i] = PiThreadNotifyRoutine[i];
   }
   NotifyRoutineCount = PiThreadNotifyRoutineCount;
#endif /* LIBCAPTIVE */
   KeReleaseSpinLock(&PiThreadListLock, oldIrql);

   Thread->Tcb.BasePriority = Thread->ThreadsProcess->Pcb.BasePriority;
   Thread->Tcb.Priority = Thread->Tcb.BasePriority;

#ifndef LIBCAPTIVE
  for (i = 0; i < NotifyRoutineCount; i++)
  {
      //must be called below DISPATCH_LVL
      NotifyRoutine[i](Thread->Cid.UniqueProcess,
			       Thread->Cid.UniqueThread,
			       TRUE);
  }
#endif /* LIBCAPTIVE */

  return(STATUS_SUCCESS);
}

#ifndef LIBCAPTIVE

static NTSTATUS
PsCreateTeb(HANDLE ProcessHandle,
	    PTEB *TebPtr,
	    PETHREAD Thread,
	    PUSER_STACK UserStack)
{
   MEMORY_BASIC_INFORMATION Info;
   NTSTATUS Status;
   ULONG ByteCount;
   ULONG RegionSize;
   ULONG TebSize;
   PVOID TebBase;
   TEB Teb;
   ULONG ResultLength;

   TebBase = (PVOID)0x7FFDE000;
   TebSize = PAGE_SIZE;

   while (TRUE)
     {
	Status = NtQueryVirtualMemory(ProcessHandle,
				      TebBase,
				      MemoryBasicInformation,
				      &Info,
				      sizeof(Info),
				      &ResultLength);
	if (!NT_SUCCESS(Status))
	  {
	     CPRINT("NtQueryVirtualMemory (Status %x)\n", Status);
	     KEBUGCHECK(0);
	  }
	/* FIXME: Race between this and the above check */
	if (Info.State == MEM_FREE)
	  {
	     /* The TEB must reside in user space */
	     Status = NtAllocateVirtualMemory(ProcessHandle,
					      &TebBase,
					      0,
					      &TebSize,
					      MEM_RESERVE | MEM_COMMIT,
					      PAGE_READWRITE);
	     if (NT_SUCCESS(Status))
	       {
		  break;
	       }
	  }
	     
	TebBase = TebBase - TebSize;
     }

   DPRINT ("TebBase %p TebSize %lu\n", TebBase, TebSize);

   RtlZeroMemory(&Teb, sizeof(TEB));
   /* set all pointers to and from the TEB */
   Teb.Tib.Self = TebBase;
   if (Thread->ThreadsProcess)
     {
        Teb.Peb = Thread->ThreadsProcess->Peb; /* No PEB yet!! */
     }
   DPRINT("Teb.Peb %x\n", Teb.Peb);
   
   /* store stack information from UserStack */
   if(UserStack != NULL)
   {
    /* fixed-size stack */
    if(UserStack->FixedStackBase && UserStack->FixedStackLimit)
    {
     Teb.Tib.StackBase = UserStack->FixedStackBase;
     Teb.Tib.StackLimit = UserStack->FixedStackLimit;
     Teb.DeallocationStack = UserStack->FixedStackLimit;
    }
    /* expandable stack */
    else
    {
     Teb.Tib.StackBase = UserStack->ExpandableStackBase;
     Teb.Tib.StackLimit = UserStack->ExpandableStackLimit;
     Teb.DeallocationStack = UserStack->ExpandableStackBottom;
    }
   }

   /* more initialization */
   Teb.Cid.UniqueThread = Thread->Cid.UniqueThread;
   Teb.Cid.UniqueProcess = Thread->Cid.UniqueProcess;
   Teb.CurrentLocale = PsDefaultThreadLocaleId;

   /* Terminate the exception handler list */
   Teb.Tib.ExceptionList = (PVOID)-1;
   
   DPRINT("sizeof(TEB) %x\n", sizeof(TEB));
   
   /* write TEB data into teb page */
   Status = NtWriteVirtualMemory(ProcessHandle,
                                 TebBase,
                                 &Teb,
                                 sizeof(TEB),
                                 &ByteCount);

   if (!NT_SUCCESS(Status))
     {
        /* free TEB */
        DPRINT1 ("Writing TEB failed!\n");

        RegionSize = 0;
        NtFreeVirtualMemory(ProcessHandle,
                            TebBase,
                            &RegionSize,
                            MEM_RELEASE);

        return Status;
     }

   if (TebPtr != NULL)
     {
        *TebPtr = (PTEB)TebBase;
     }

   DPRINT("TEB allocated at %p\n", TebBase);

   return Status;
}

VOID STDCALL
LdrInitApcRundownRoutine(PKAPC Apc)
{
   ExFreePool(Apc);
}

VOID STDCALL
LdrInitApcKernelRoutine(PKAPC Apc,
			PKNORMAL_ROUTINE* NormalRoutine,
			PVOID* NormalContext,
			PVOID* SystemArgument1,
			PVOID* SystemArgument2)
{
  ExFreePool(Apc);
}

NTSTATUS STDCALL
NtCreateThread(PHANDLE ThreadHandle,
	       ACCESS_MASK DesiredAccess,
	       POBJECT_ATTRIBUTES ObjectAttributes,
	       HANDLE ProcessHandle,
	       PCLIENT_ID Client,
	       PCONTEXT ThreadContext,
	       PUSER_STACK UserStack,
	       BOOLEAN CreateSuspended)
{
  PETHREAD Thread;
  PTEB TebBase;
  NTSTATUS Status;
  PKAPC LdrInitApc;

  DPRINT("NtCreateThread(ThreadHandle %x, PCONTEXT %x)\n",
	 ThreadHandle,ThreadContext);

  Status = PsInitializeThread(ProcessHandle,
			      &Thread,
			      ThreadHandle,
			      DesiredAccess,
			      ObjectAttributes,
			      FALSE);
  if (!NT_SUCCESS(Status))
    {
      return(Status);
    }

  Status = KiArchInitThreadWithContext(&Thread->Tcb, ThreadContext);
  if (!NT_SUCCESS(Status))
    {
      return(Status);
    }

  Status = PsCreateTeb(ProcessHandle,
		       &TebBase,
		       Thread,
		       UserStack);
  if (!NT_SUCCESS(Status))
    {
      return(Status);
    }
  Thread->Tcb.Teb = TebBase;

  Thread->StartAddress = NULL;

  if (Client != NULL)
    {
      *Client = Thread->Cid;
    }

  /*
   * Maybe send a message to the process's debugger
   */
  DbgkCreateThread((PVOID)ThreadContext->Eip);

  /*
   * First, force the thread to be non-alertable for user-mode alerts.
   */
  Thread->Tcb.Alertable = FALSE;

  /*
   * If the thread is to be created suspended then queue an APC to
   * do the suspend before we run any userspace code.
   */
  if (CreateSuspended)
    {
      PsSuspendThread(Thread, NULL);
    }

  /*
   * Queue an APC to the thread that will execute the ntdll startup
   * routine.
   */
  LdrInitApc = ExAllocatePool(NonPagedPool, sizeof(KAPC));
  KeInitializeApc(LdrInitApc, &Thread->Tcb, OriginalApcEnvironment, LdrInitApcKernelRoutine,
		  LdrInitApcRundownRoutine, LdrpGetSystemDllEntryPoint(), 
		  UserMode, NULL);
  KeInsertQueueApc(LdrInitApc, NULL, NULL, IO_NO_INCREMENT);

  /*
   * Start the thread running and force it to execute the APC(s) we just
   * queued before it runs anything else in user-mode.
   */
  Thread->Tcb.Alertable = TRUE;
  Thread->Tcb.Alerted[0] = 1;
  PsUnblockThread(Thread, NULL);

  return(STATUS_SUCCESS);
}


/*
 * @implemented
 */
NTSTATUS STDCALL
PsCreateSystemThread(PHANDLE ThreadHandle,
		     ACCESS_MASK DesiredAccess,
		     POBJECT_ATTRIBUTES ObjectAttributes,
		     HANDLE ProcessHandle,
		     PCLIENT_ID ClientId,
		     PKSTART_ROUTINE StartRoutine,
		     PVOID StartContext)
/*
 * FUNCTION: Creates a thread which executes in kernel mode
 * ARGUMENTS:
 *       ThreadHandle (OUT) = Caller supplied storage for the returned thread 
 *                            handle
 *       DesiredAccess = Requested access to the thread
 *       ObjectAttributes = Object attributes (optional)
 *       ProcessHandle = Handle of process thread will run in
 *                       NULL to use system process
 *       ClientId (OUT) = Caller supplied storage for the returned client id
 *                        of the thread (optional)
 *       StartRoutine = Entry point for the thread
 *       StartContext = Argument supplied to the thread when it begins
 *                     execution
 * RETURNS: Success or failure status
 */
{
   PETHREAD Thread;
   NTSTATUS Status;
   
   DPRINT("PsCreateSystemThread(ThreadHandle %x, ProcessHandle %x)\n",
	    ThreadHandle,ProcessHandle);
   
   Status = PsInitializeThread(ProcessHandle,
			       &Thread,
			       ThreadHandle,
			       DesiredAccess,
			       ObjectAttributes,
			       FALSE);
   if (!NT_SUCCESS(Status))
     {
	return(Status);
     }
   
   Thread->StartAddress = StartRoutine;
   Status = KiArchInitThread(&Thread->Tcb, StartRoutine, StartContext);
   if (!NT_SUCCESS(Status))
     {
	return(Status);
     }

   if (ClientId != NULL)
     {
	*ClientId=Thread->Cid;
     }

   PsUnblockThread(Thread, NULL);
   
   return(STATUS_SUCCESS);
}


/*
 * @implemented
 */
NTSTATUS STDCALL
PsSetCreateThreadNotifyRoutine(IN PCREATE_THREAD_NOTIFY_ROUTINE NotifyRoutine)
{
  KIRQL oldIrql;

  KeAcquireSpinLock(&PiThreadListLock, &oldIrql);
  if (PiThreadNotifyRoutineCount >= MAX_THREAD_NOTIFY_ROUTINE_COUNT)
  {
    KeReleaseSpinLock(&PiThreadListLock, oldIrql);
    return(STATUS_INSUFFICIENT_RESOURCES);
  }

  PiThreadNotifyRoutine[PiThreadNotifyRoutineCount] = NotifyRoutine;
  PiThreadNotifyRoutineCount++;
  KeReleaseSpinLock(&PiThreadListLock, oldIrql);

  return(STATUS_SUCCESS);
}

#endif /* LIBCAPTIVE */

/* EOF */